package edu.ecust.design.utils;

import java.security.MessageDigest;

import javax.servlet.http.HttpServletRequest;

import org.apache.log4j.Logger;

import edu.ecust.design.cons.AccountContext;
import edu.ecust.design.domain.Account;

/**
 * 帐号的相关工具类
 * 
 * @author fei
 * 
 */
public class AccountUtils {
	private static final Logger logger = Logger.getLogger(AccountUtils.class);

	/**
	 * MD5算法，用于密码加密
	 * 
	 * @param s
	 * @return
	 */
	public final static String MD5(String s) {
		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
				'A', 'B', 'C', 'D', 'E', 'F' };
		try {
			byte[] btInput = s.getBytes();
			// 获得MD5摘要算法的 MessageDigest 对象
			MessageDigest mdInst = MessageDigest.getInstance("MD5");
			// 使用指定的字节更新摘要
			mdInst.update(btInput);
			// 获得密文
			byte[] md = mdInst.digest();
			// 把密文转换成十六进制的字符串形式
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e) {
			logger.error("MD5 error", e);
			return null;
		}
	}

	public static Account getAccountBySession(HttpServletRequest request) {
		return (Account) request.getSession().getAttribute(
				AccountContext.session.getText());
	}

	public static void main(String[] args) {
		System.out.println(AccountUtils.MD5("111111"));
	}
}
